JPH02233942A - Heat exchanger for hot water feeder - Google Patents

Abstract

PURPOSE:To improve an efficiency of the heat exchanger and make a compact heat exchanger by a method wherein a length of each of resistors within smoke tubes located far as viewed from a burner arranged on a side wall part of a combustion chamber is shortened and a length of each of inhibitors within each of the smoke pipes placed at an operator's side is elongated. CONSTITUTION:Combustion gas generated from a burner 3 arranged at a side wall of a combustion chamber 1 strikes against an opposing water boiler wall 2, its direction is changed to face upwardly and then the combustion gas passes through some smoke pipes 4. The combustion gas flowing within the smoke pipes 4 placed far as viewed from the burner shows a higher temperature and the combustion gas at the operator's side shows a lower temperature. Accordingly, in compliance with a temperature distribution of this combustion gas, the lower end position of each of the resistors 5 within each of the smoke pipes 4 far as viewed from the burner is high to provide shorter resistors. As a result, a length of each of the resistors 5 is lengthened in order that the lower end position of each of the resistors 5 within the pipes 4 placed at the operator's side as viewed from the burner is lower, an efficiency of a heat exchanger can be improved without providing any upgrading of the material of each of the resistors and without increasing a size of the heat exchanger.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat exchanger for a water heater installed mainly in a domestic oil water heater. 2. Description of the Related Art A conventional heat exchanger for a water heater has a smoke pipe 2 as shown in FIG.
1 is provided with a resistor 22 in order to promote heat exchange between water and combustion gas on the passage wall. It is necessary to place the lower end 24 at a position where the temperature does not exceed the heat resistance temperature of the material of the resistor 22 when it is heated. Therefore, among the many resistors 22 in the smoke pipe 21, find the resistor 22 whose temperature rises the most and remove that resistor. The distance from the burner 23 was set so that the temperature at the lower end 24 of the resistor 22 did not exceed the heat-resistant temperature, and the other resistors 22 were designed accordingly.
Problem to be Solved by the Invention However, the temperature at the lower end 24 of the resistor 22 is
The temperature of the resistor 22 in a position that is difficult to heat with combustion gas is still lower than the heat-resistant temperature of the material, so if the position is lowered further,
The area where heat exchange between water and combustion gas is promoted can be expanded using the passage walls, which could further improve heat exchange efficiency, but it has not been used effectively. The present invention solves the above problems by changing the lower end position of the resistor depending on the position of the smoke pipe, that is, changing the length of the resistor to improve the efficiency of the heat exchanger, thereby making the heat exchanger more compact. The purpose is to measure the Means for Solving the Problems In order to solve the above problems, the water heater heat exchanger of the present invention includes a cylindrical combustion chamber having a water can wall around it, a burner provided on the side wall of the combustion chamber, and a combustion chamber. It is equipped with a number of smoke pipes that allow combustion gas to pass through the upper part of the chamber and exchange heat with water on the passage walls, and a resistor installed inside the smoke pipes, and is located further away from the burner installed on the side wall of the combustion chamber. The length of the resistor inside the smoke pipe is shortened, and the length of the resistor inside the smoke pipe in front is lengthened. Effect With the above configuration, the lower end position of the resistor can be changed depending on the position of the burner and the smoke pipe, that is, the length of the resistor can be changed to improve the efficiency of the heat exchanger, thereby making it possible to make the heat exchanger more compact. Become. EXAMPLE Hereinafter, an example of the present invention will be explained based on the drawings. In Fig. 1, l is a cylindrical combustion chamber with a water can wall 2 around it, 3 is a burner installed on the side wall of the combustion chamber l, and 4 is a passage wall that allows combustion gas to pass through the upper part of the combustion chamber. A smoke pipe 5 provided for exchanging heat with water is a resistor installed within the smoke pipe 4 to promote heat transfer between the combustion gas and the passage wall. 6 is a water supply port provided on the side of the water heater heat exchanger, and 7 is a hot water supply port. In the above configuration, the flame formed in the burner 3 becomes combustion gas, exchanges heat with water on the surface of the water can wall 2 of the combustion chamber 1, and promotes heat transfer by the resistor 5 on the passage wall of the numerous smoke pipes 4. It exchanges heat with water and is discharged. On the other hand, water entering from the water supply port 6 undergoes heat exchange between the water can wall 2 and the passage wall of the smoke pipe 4, and is then supplied from the hot water supply port 7. Combustion gas generated from a burner 3 provided on the side wall of the combustion chamber 1 hits the opposing water can wall 2, changes direction upward, and passes through the smoke pipe 4. Therefore, among the many smoke pipes 4 provided, the temperature of the combustion gas flowing through the smoke pipes 4 located further away from the burner is higher, and the temperature is lower in the smoke pipes 4 closer to the burner. It is more advantageous for heat exchange if the resistor 5 in the smoke tube 4 is provided all the way to the bottom of the smoke tube 4, but since it will be heated by the combustion gas, it should not exceed the heat resistance temperature of the material of the resistor 5. If the resistor 5 is lowered too far to the bottom of the smoke pipe 4, the temperature will rise too much. Therefore, in accordance with the temperature distribution of the combustion gas, the length is shortened so that the lower end position of the resistor 5 in the smoke tube 4, which is far from the burner, is higher, and the resistor in the smoke tube 4, which is in front of the burner, is shortened. 5 is a heat exchanger without upgrading the material of the resistor 5 or increasing the size of the heat exchanger by increasing the length of the resistor 5 so that the lower end position is lower. It is possible to measure the efficiency improvement of Effects of the Invention As is clear from the above description of the embodiments, the heat exchanger for water heaters of the present invention does not require increasing the resistance material, and it is possible to increase the size of the heat exchanger. This has the effect of improving the efficiency of the heat exchanger and making it compact in the most economical way without having to do anything.

[Brief explanation of the drawing]

Figure 1 shows a heat exchanger lII for a water heater in one embodiment of the present invention.
! A cross-sectional view showing the vessel, Figure 2 is a view in the direction of arrow A in Figure 1,
FIG. 3 is a perspective view of a resistor, and FIG. 4 is a sectional view showing a conventional heat exchanger for a water heater. l... Combustion chamber, 2... Water can wall, 3...
... Burner, 4 ... Smoke pipe, 5 ...
Resistor. Name of agent: Patent attorney Shigetaka Awano

Claims (1)

[Claims] A cylindrical combustion chamber with a water can wall around it, a burner installed on the side wall of the combustion chamber, and a large number of combustion chambers that allow combustion gas to pass through the upper part of the combustion chamber and exchange heat with water on the passage wall. A smoke pipe and a resistor provided in the smoke pipe, the length of the resistor in the smoke pipe that is far from the burner provided on the side wall of the combustion chamber is shortened, and the resistor in the smoke pipe that is in front of the burner is shortened. A heat exchanger for a water heater, characterized by having a longer length.